A robotic vacuum cleaner forms of a self-propelling unit provided with a drive arrangement comprising a control system configured to control a movement of the robotic vacuum cleaner along a surface to be cleaned. The control system may comprise one or more sensors providing input to assist in controlling the movement of the robotic vacuum cleaner. A vacuum producing unit of the robotic vacuum cleaner is arranged in fluid communication with an opening of a nozzle inlet facing the surface to be cleaned. Debris sucked or otherwise propelled into the opening is directed into a debris receptacle of the robotic vacuum cleaner. The debris receptacle is emptied, or replaced, when filled with debris to a certain degree.
Since a robotic vacuum cleaner is to move freely about a surface to be cleaned it would be limited in its movements by an electric cord. Thus, a robotic vacuum cleaner is battery powered and the cleaning capability of a robotic vacuum cleaner has to be designed with the capacity of the on-board battery in mind. Accordingly, the drive arrangement, the capacity of the vacuum producing unit, the use of various rotating brushes, etc. affect consumption of electric power and thus, the design of a robotic vacuum cleaner.
Some robotic vacuum cleaners are provided with a rotatable side brush extending beyond a housing of the robotic vacuum cleaner. The rotatable side brush is arranged to brush debris from an area beside the housing and the nozzle inlet to the nozzle inlet, or at least within reach of a suction produced around the nozzle inlet by the vacuum producing unit.
Such a rotatable side brush should not impede the movement of the robotic vacuum cleaner. Thus, in a robotic vacuum cleaner comprising a rotatable side brush, design considerations include selecting a position of the rotatable side brush to not hinder the movement of the robotic vacuum cleaner, and selecting a clearance to the surface to be cleaned to permit the rotatable side brush to rotate more or less freely underneath the housing of the robotic vacuum cleaner. Accordingly, the position of the rotatable side brush and the clearance to the surface to be cleaned may not be optimal from a cleaning efficiency perspective. Moreover, use of a rotatable side brush may influence other design measures affecting the cleaning capacity of the robotic vacuum cleaner, or the battery capacity of the robotic vacuum cleaner.